BankAlt.com offers a simple concept. Have you ever tried to calculate what components you need for a certain recipe/pattern/schematic in World of Warcraft? How about what sub-components are required for the main components?
If the mere thought of calculating all the sub-sub-sub-... components needed to craft something more complex is giving you a headache, BankAlt's profession and tradeskill calculator makes it all simple.
To get started, click on the profession of your choice. A list of recipes/patterns/schematics for that profession with the main crafting components will appear. Clicking the "Quick Tree" link will drill down further into each component, provided that it isn't an "end item". Sub-components are indented depending on how deep they are. The total quantity of components required to craft the main item is shown next to each component.
The "Full Tree" link brings up a window with the full hierarchy of materials, plus gold/silver/copper boxes which allows you to enter your costs. As you type, the total cost for the main recipe is calculated automatically.
You can save the cost of components for later retrieval. You can restore saved costs later for a component, which will re-calculate the total price for the recipe based on the restored amount.
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